Praseodymium vs Berkelium

PropertyPr PraseodymiumBk Berkelium
Atomic number5997
SymbolPrBk
NamePraseodymiumBerkelium
Categorylanthanideactinide
Standard Atomic Weight140.90766 u247 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f3[Rn]7s25f9
Oxidation states[0, 1, 2, 3, 4, 5][2, 3, 4, 5]
Electronegativity (Pauling)1.131.3
Electron affinity0.962 eV-0.5 eV
Density6770 kg/m³1.400000e+4 kg/m³
Melting point930.85 °C1049.85 °C
Boiling point3519.85 °C-273.15 °C
Discovery year18851949